In the brewing of beer, which is one kind of alcoholic beverage, there are four processes; a preparation process, a fermentation process (main fermentation process), a storage process (subsequent fermentation process) and a filtration process. In the preparation process, wort is formed by boiling hot water containing malt and filtering the same to remove impurities contained therein. Next, the wort is fermented in the fermentation process by adding yeast thereto after being cooled. Then, the fermented malt beverage immediately after the fermentation; i.e., young beer is matured in the storage process, and the matured fermented malt beverage such as beer thus obtained is filtered in the filtration process. Finally, the filtered beer is filled in cans or others by a filler (not shown), after which the cans or others are tightly sealed by a seamer and shipped as products.
In this regard, in each of the above-mentioned four processes, a cooling treatment is carried out, to a predetermined temperature, depending on the respective process. In the preparation process, of the four processes, the cooling treatment is carried out with relatively low temperature water such as well water until the malt juice temperature reaches approximately 20° C. Since a lower temperature is required, in some of the above processes, than the cooling temperature attained by using well water in the preparation process, however, a cooling system achieving such a low temperature must be used. Note that the cooling temperature in these processes becomes lower in the order of the preparation process, the fermentation process, the storage process and the filtration process.
FIG. 5 schematically illustrates a cooling system based on the prior art. As shown in FIG. 5, the cooling system 100 based on the prior art includes a heat-storage tank 200 filled with a coolant, such as brine which is a glycol-type antifreeze. The heat-storage tank 200 is cooled, through a passage 220, by a refrigerator group 210. As illustrated, in the prior art cooling system 100, three circulating passages 110, 120 and 130 arranged generally parallel to each other are connected to the heat-storage tank 200. These circulating passages 110, 120 and 130 are connected to three loads to be cooled, that is, a low thermal load 113, a medium thermal load 123 and a high thermal load 133, respectively, and heat is exchanged therewith. The temperature of the load to be cooled becomes higher in the order of the low thermal load 113, the medium thermal load 123 and the high thermal load 133, wherein the low thermal load 113 corresponds to the storage process and the filtration process during the brewing beer, the medium thermal load 123 to the fermentation process, and the high thermal load 133 to the preparation process, respectively.
In the cooling system 100 shown in FIG. 5, the brine in the heat-storage tank 200 is cooled by the refrigerator group 210 to a temperature lower than that necessary for the low thermal load 113. Then, the cooled brine circulates through the circulating passages 110, 120 and 130 by pumps not shown, whereby the low thermal load 113, the medium thermal load 123 and the high thermal load 133 can be properly cooled, respectively, while the brine is passing through the circulating passages 110, 120 and 130.
However, as all of the low thermal load 113, the medium thermal load 123 and the high thermal load 133 are cooled by means of a single refrigerator group 210 in the cooling system 100 shown in FIG. 5, it is needed to cool the brine in the heat-storage tank 200 to a temperature lower than that necessary for cooling the low thermal load 113. Thus, the medium thermal load 123 and the high thermal load 133 are cooled with the brine cooled at a lower temperature than required. In other words, in the prior art cooling system 100, there is a large energy loss in the cooling operation because the refrigerator group 210 suitable for generating the low temperature necessary for the low thermal load 113 is also used for cooling the medium thermal load 123 and the high thermal load 133. Also, in the prior art cooling system 100, as a single refrigerator group 210 is used for cooling all of the low thermal load 113, the medium thermal load 123 and the high thermal load 133, a long time and much energy are required until the brine has been cooled to a predetermined temperature, which largely increase the running cost of the refrigerator group 210. Furthermore, the brine having a relatively high viscosity is circulated by a pump through all the circulating passages 110, 120 and 130, which results in the large energy loss.
In this regard, when refreshing beverages other than alcoholic beverage, such as oolong tea drink, green tea drink, carbonated drink or coffee drink are produced, cooling treatments may be carried out in some processes. Of these cooling treatments, there are cases in which well water is used as a coolant. In most of these cooling treatments, a temperature corresponding to those of the medium thermal load 123 or the high thermal load 133 when the beer is brewed, is necessary. Accordingly, a cooling system similar to that described above is necessary in the process for producing beverages other than an alcoholic beverage. In this regard, while the above-mentioned temperature necessary for cooling of the low thermal load 113 is lower than 0° C., it is impossible to cool beverages other than an alcoholic beverage to such a low temperature because of freezing, whereby the low thermal load 113 does not need to be taken into account.
FIG. 6 schematically illustrates a cooling system used for the production of beverages other than an alcoholic beverage. The cooling system 300 shown in FIG. 6 is provided with a heat-storage tank 400 filled with water. This heat-storage tank 300 is cooled, by means of a refrigerator group 410, through a passage 420. Also, as illustrated, in the prior art cooling system 300, two circulating passages 320 and 330 arranged generally parallel to each other are connected to the heat-storage tank 400. The circulating passage 320 is connected to an medium thermal load 323, while the circulating passage 330 is connected to a high thermal load 333. The cooling temperature required for the medium thermal load 323 and the high thermal load 333 becomes higher in this order.
According to the cooling system 300 shown in FIG. 6, water in the heat-storage tank 400 is cooled by the refrigerator group 410 to a temperature lower than that necessary for the medium thermal load 323. Then, the cooled water circulates through the circulating passages 320 and 330 by means of a pump not shown. Accordingly, it is possible to properly cool the medium thermal load 323 by the circulation of water through the circulating passage 320, and to properly cool the high thermal load 333 by the circulation of water through the circulating passage 330. Note that each of the medium thermal load 323 and the high thermal load 333 in the cooling system 300 shown in FIG. 6 is different, in temperature, in accordance with kinds of beverages produced by this system. While only two kinds of thermal loads; that is, the medium thermal load 323 and the high thermal load 333; are shown in the cooling system 300 in FIG. 6, there may be a case wherein the kinds of the thermal loads increase or decrease; i.e., either one of the medium thermal load 323 and the high thermal load 333 may be eliminated.
As is well known, an alcoholic beverage, for example beer, is produced in a beer factory exclusive designed therefor, and general beverage containing no alcohol, such as oolong tea drink, green tea drink, carbonated drink or coffee drink is produced in a beverage-producing factory other than a beer factory. Recently, it has been contemplated to centralize a beer factory and another beverage-producing factory in the same site. In such a case, it is expected to have such advantages that beer and the other beverage could be stored in the same storehouse and the same devices could be used for the both in part of the production process such as an inspection process.
When the above-mentioned cooling system 100 or 300 is commonly adopted for the productions of beer and the non-alcoholic beverage, however, there may be the following disadvantages:
Assuming that the cooling system 100 used for brewage of beer is also used simultaneously in the process for producing a non-alcoholic beverage, as there is no low thermal load when producing general beverage containing no alcohol, only a capacity necessary for cooling the medium thermal load 123 and the high thermal load 133 increases more than that needed for brewing beer. However, as the cooling system 100 is designed to cool all of the low thermal load 113, the medium thermal load 123 and the high thermal load 133 by a single refrigerator group 210, it is necessary to increase a capacity for cooling the low thermal load 113 for the purpose of increasing capacities for cooling the medium thermal load 123 and the high thermal load 133, even if it is unnecessary to increase the capacity for cooling the low thermal load, whereby the size of the refrigerator group 210 must be larger. A temperature necessary for cooling the low thermal load 113 is lower than 0° C., and brine is used for achieving such a low temperature. Accordingly, the increase in capacity for cooling the low thermal load 113 in the production line for non-alcoholic drink in which no low thermal load exists, results in a large energy loss.
On the other hand, if the cooling system 300 used for the production of non-alcoholic beverage is also used simultaneously for the brewage of beer the cooling system 300 cannot be used for brewing beer because there is no means for cooling the low thermal load 113 in the cooling system 300. For the above-mentioned reasons, the development of a novel cooling system commonly usable for brewing beer and the production of the other beverage has been desired.
The present invention has been made under such circumstances, and an object thereof is to provide an advantageous cooling system capable of reducing its energy loss, particularly in the cooling treatment during brewing beer and the production of another beverage.